When employing an electron beam emitter to irradiate objects, materials, substances, etc. with electron beams within gaseous atmospheres such as air, or behind an object, it is sometimes desirable to determine the intensity of the electron beam which actually reaches the subject of irradiation. Current methods of measuring include placing a calibrated sheet or film of electron sensitive material (dosemeter) in the path of the electron beam and then removing the sheet for visual inspection and measurement. Such a method is cumbersome and is not suitable for continuous monitoring of the electron beam in real time, or for use while processing material during manufacturing.